> weird keyboard mappings for things like "start of line", "end of line", "previous word"

Those are Emacs keybindings, and they're also present by default in Bash since they were copied by GNU Readline. They're one of the few things I really like about macOS. (But I'm an Emacs user and I'm also used to using them in my terminal.)

The window manager never stops sucking. Rectangle and Contexts or Witch help. Ice helps with the stupid menu bar design and problems with overflowing icons or oversized menus.